This invention relates to the field of archery. More particularly, it relates to arrow rest devices involved in accurate shooting of the new, faster, and more powerful bows of today. Archers may participate in several forms of shooting. The two most popular activities, bow hunting and target shooting, are greatly improved by arrow rests which provide little or no interference with an arrow being shot by the bow.
Bows and arrows rank among man""s oldest weapons, with the prehistoric man shooting game for their subsistence. Many types of bows were developed, including the short bow, English longbow, and the cross bow that came about in the middle ages. More recent has been the development of the compound bow that has greatly advanced the field archery. Every year between 1,500,000 and 4,000,000 people in Canada and the United States go bow hunting or take part in some form of archery competition. The sport has become especially popular in schools and colleges. The summer Olympic games included an archery competition from 1896 until the sport was dropped following the 1920 games. Archery was reintroduced in the 1972 summer Olympic games and still remains very popular today.
The two most popular archery activities are bow hunting and target shooting. In bow hunting, the archers hunt game with just the bow and arrow. Bow season usually precedes the regular hunting season, giving the archers some distinct advantages.
In target shooting, the archer shoots at a target to score points in competition with other archers. When an archer prepares to shoot, the arrow shaft is conventionally positioned on an arrow rest of some kind, the bowstring is set within the arrow nock, and the bowstring and arrow are drawn back. The archer aims through the area above the rest and beside the bow riser section called the window region. After the arrow is released and it passes by the position of the rest, a common occurrence is for the fletches or plastic vanes to strike the rest moving it out of the way. This causes the arrow to be deflected and wobble in flight. Very light weight carbon graphite arrows are often used adding to the problem when such arrows are deflected, even in the slightest.
For the avid archer that is striving for perfection this deflection by the rest during traverse of the arrow is a major problem and can only be resolved by some form of retracting arrow rest which moves to avoid contact with the moving arrow. Other rests incorporate a stationary or flexible element that the arrow is held against and these devices also have an undesirable effect on the flight of the arrow.
Various other types of drop away rests have been previously created. All share a feature that allow the arrow support arm to move out of the path of the arrow shaft and fletching when the arrow is released by the archer. Some of the other current designs depend on the arrow support arm to be pulled into the upright position when the bow is drawn, and to spring back out of the way when the arrow is released. This is accomplished by a physical connection from the arrow rest to either the cable slide or cable of a compound bow. The physical connection is in the form of a string, rubber tubing, or other similar item. There are a number of problems with this system of lifting the arrow supports arms. Strings can snag on branches while in the field or restrict the length the arrow can be drawn back, the rubber tubing can crack from exposure to UV light or break without warning, all can cause maladjustment or failure of the system.
The disclosed device herein generally relates to a device for improving the accuracy and refining the arrow rests for either bows or crossbows. More specifically, it relates to an improved magnetic drop-away arrow rest retro-fit conversion kit to be attached to the crossbar support block or which can be manufactured and attached to the support block at the factory as original equipment. The reason for the drop-away rest is to support the arrow, then to move completely away upon release before the fletches or vanes pass over the rest so they will not be damaged or the accuracy of the arrows flight affected.
U.S. Pat. No. 3,342,173 of Eugene L. Ferguson describes an arrow rest that is magnetically held in a position to support the arrow prior to being released. Upon release of the arrow, as the fletches or vanes pass the supporting means they will strike it, causing the release of the magnet and the supporting means will pivot to the side against the bow riser, out of the way to be manually reset. The action of the feathers or vanes striking anything, and the rest passing under the arrow, has the tendency to cause the arrow to wobble, affecting the accuracy of the shot.
U.S. Pat. No. 4,343,286 of Bobby J. Thacker teaches of a bow, the center of which is constructed to permit an unimpeded, dead center flight of the arrow as it leaves the bow. This unique, unconventional bow and arrow has a cumbersome magnetic system with a special magnetically attracted point or pile for retracting the arrow rest out of the way as the arrow passes. This device would be difficult to adapt to any conventional bow and would require the archers to purchase special bows and arrows.
U.S. Pat. No. 4,473,058 of Edgell R. Terry discloses a bow and arrow rest, which includes a wire that is pivotally mounted near the middle of the bow. The wire is held in, place by a magnet that supports the arrow against a fixed support. When the arrow is released and the rest pivots under the arrow and out of the way against the bow riser, the support remains in a fixed position against the arrow. There is also no adjustment to the magnetic contact on the wire rest for arrows of different diameters or to fine tune the release mechanism.
U.S. Pat. No. 4,489,704 of Fernando Troncoso additionally describes an arrow rest that is spring or magnetically loaded to hold the arrow with a curve in the end of a wire support member against an adjustable plunger. Although all portions of this device are fully adjustable, when the device is set up and the arrow is released, the arrow still rides against the plunger as it passes the rest and the wire rest pivots under the arrow to the side against the riser.
U.S. Pat. No. 4,548,189 of Mitchell E. Pietraszek describes a ferromagnetic wire rest member that is pivotally attached to a mounting bracket and is biased into operative position. A permanent magnet permits the rest pin to be deflected from the operative position by the fletches of an arrow passing across the rest pin. This is another device that allows the rest to engage the fletches causing a wobble of the arrow during flight and affecting the accuracy of the shot.
U.S. Pat. No. 4,860,719 of Ernst Scheiterlein teaches of a hold down device for a crossbow arrow or bolt using a magnetic support and adjustably positionable in the tray beneath the ferro-magnetic arrowhead to hold the arrow against the arrow rest. This device is designed specifically for crossbows and has adjustment of the spacing of the magnet away from the arrowhead, but it does not describe any unique features in the rest for the arrow and would not function on a conventional bow.
U.S. Pat. No. 5,503,136 of Richard D. Tone discloses an invention that relates to an arrow support mechanism including an arrow rest arm that is magnetically, weight, or spring-biased inward toward the side of the bow window so as to retract out of the path of a vane of the arrow just after it is released. With this patent, a rest arm that is slightly curved upward retains the arrow against an elastic xe2x80x9cspine pointxe2x80x9d arm. Upon release, the curved end has to pass under the arrow to be retracted against the side of the bow riser section while still being held against the elastic xe2x80x9cspine pointxe2x80x9d arm, both of which have adverse effects on the flight of the arrow.
U.S. Pat. No. 5,601,069 of James F. Clark teaches of an arrow rest consisting of an articulated or telescoping pin having a spring-loaded retract mechanism to the side against the bow riser. This sideways movement of the arrow rest has a noticeable adverse effect on the flight of the arrow.
U.S. Pat. No. 5,606,961 of Ronald Basik describes an arrow rest that relies upon the friction of the arrow against the pivoting body member when the arrow is propelled by the bowstring. This arrow rest pivots down and out of the way, in the direction of the travel of the arrow flight, and it uses a rubber band or spring biasing over-center action as a release means with the option of using two attracting magnets in direct contact to hold the mechanism open or closed. With the magnets held in direct contact there is no means to fine-tune the release capabilities of the device. This device also cannot be used as a conversion kit for any other manufacturer""s arrow rest assemblies.
U.S. Pat. No. 5,606,962 of Vincent Troncoso discloses an arrow rest that also rotates down forward and out of the way when the archer releases an arrow. This patent deals strongly with the horseshoe style of support arms and their unique capabilities, but it does not have a means to fine-tune the release mechanism.
U.S. Pat. No. 6,082,348 of Huey P. Savage tells of an arrow shaft support that pivots away from the arrow shaft with sufficient speed to prevent any of the arrow vanes from striking any of the arrow shaft supports. This system also drops away in front of the path of the arrow and has an adjustable tension on a biasing spring, but has the magnet in contact in the cocked position, and is not adaptable as a conversion kit for any other manufacturers arrow rest assemblies. Another flaw is that the length of the magnetic contact arm is so long that when the rest operates there can be contact with the archers thumb in some bow configurations.
Existing drop away rests that hold the arrow support in the upright position with magnetic force, as in U.S. Pat. No. 6,082,348 (Savage), also suffer from various design impediments. Among the flaws of this design is a long heavy magnetic contact arm. The arrow support arm must pivot out of the path of the shaft and arrow fletching. The inertial mass caused by the weight and length of the magnetic contact arm in the existing design causes the pivot action to be slow, thus, with extremely fast bows, the rest support arms will not drop in time to clear the fletching. This design calls for direct physical contact between the magnet and the magnetic contact arm, effectively eliminating any adjustment of the magnet force required to break said contact. This is an extremely limiting feature of the current design, as there is no adjustment for differences in arrow shaft or point weights. Additionally, the magnetic contact arm is designed to function on either a right or a left handed rest but not both. Another problem is that the length of the magnetic contact arm is so long that when the rest operates there can be contact with the archers thumb in some bow configurations, contact when an archer has a large hand, or contact when the archer is wearing a glove. Any contact can prevent the rest support arms from dropping consistently and ruining arrow accuracy.
The improved archery arrow rest of this invention provides remedies for the faults found in previous designs. By using a magnetic attraction to hold the arrow support arms in a ready position, strings or tubing that pull the arrow support arms into position are eliminated; consistency and repeatability in the positioning of the arrow support arms is achieved, improving accuracy. By utilizing magnetic attraction without actual contact, the force required to cause the biasing spring to function is reduced and the drop away action is more consistent. By utilizing a very small magnetic attraction arm that does not actually come in contact with the magnet, the speed with which the arrow support arms can move out of the path of the arrow shaft and attached fletching is increased because there is less inertial mass to overcome. By positioning the magnet on the crossbar support block and the magnetic attraction arm on the arrow support block, possible contact with the archer""s thumb, hand, or glove is totally eliminated. Additionally, the rest can be micro adjustable in both vertical and horizontal directions without affecting the orientation of the arrow support arms or the magnetic attraction arm. The magnet holder is movable in the vertical plane, thus making adjustments for magnet holding force and arrow weight simple.
None of the foregoing prior art teaches or suggests the particular combination of a first or forward biasing means such as a biasing spring, and a rearward biasing means in the form of a single magnet attracting a steel leaf and not rebuking direct contact with a steel leaf member, or, the combination of two magnets at opposite ends of the rotation, one out of direct contact when the device is in the cocked position and the other in direct contact with an adjusting screw in the released position. The biasing force to separate two magnets in direct contact can only be changed by changing the type or size of the magnets, while by maintaining a gap between, the magnets adjustments can easily be made. Thus, there is a continuing need to refine and develop new and innovative products in the field of archery.
A first preferred embodiment of the herein disclosed magnetic biased drop-away arrow rest device would be in the form of a conversion kit consisting of a number of parts that convert a conventional arrow rest into a unique magnetically biased and actuated drop-away arrow rest. These parts consist of a support-mounting block that attaches to a pivoting unit of the conventional arrow support using two mounting screws. A third screw attaches the arrow rest that can be made from a plastic material or metal. A locking screw locates the pivoting unit on a pivot shaft incorporating the biasing spring and the biasing spring adjustment knob. The biasing spring adjustment knob is held in place on the cross bar support by the means of a locking screw. The pivoting unit also incorporates the steel leaf member attached by the means of the pivot positioning screw and lock nut. The magnet support block is attached to the distal end of the cross bar support by the means of a mounting screw and registered in location by the two adjacent mating surfaces.
As the pivoting unit rotates with the pivot shaft within the cross bar support, the steel or similar magnetically attractive leaf member attached thereto comes within close proximity to the magnet on the magnet support block but does not contact the magnet, thereby maintaining a controlled gap with the magnetic attraction between the magnet and leaf member. The spacing or gap between the magnet and the steel leaf member, and the resulting amount of force of the magnetic bias, is maintained by adjusting the pivot adjustment screw against a stop located on the arm of the cross bar support. The adjustment of this spacing or gap between the magnet and the steel leaf member holding the device in the cocked position and the biasing spring pressure to release the mechanism into the drop-down position, provides a means to adjust the biasing force of the magnetic attraction overcoming the spring bias and the speed of release of the mechanism to thereby rotate quicker than if the magnet was in full contact with the steel leaf member. The thin cross sectional area of the steel leaf member allows some flexibility when reacting with the magnetic attraction of the magnet.
An alternate preferred embodiment of the device will feature a magnetic drop-away arrow rest conversion kit with dual magnet attraction, having a second magnet on the same magnet support block. As with the first preferred embodiment, the conversion kit operates with the pivoting unit rotating with the pivot shaft within the cross bar support, and the steel leaf member coming within close proximity to the magnet on the magnet support block, but not contacting the magnet. The spacing or gap between the magnet and the steel leaf member is maintained by adjusting the pivot adjustment screw against a stop located on the arm of the cross bar support as in the first embodiment. The adjustment of this spacing or gap between the magnet and the steel leaf member holding the device in the cocked position is counter acted by a second magnet attracted to the head of a steel adjusting screw drawing the device to the release position. The biasing spring used in the first embodiment will not be required in the second embodiment. Positioning of the adjustment screws and the strength of the magnets has the capability of vastly reducing the reaction time of the conventional arrow rest.
An additional preferred embodiment of the device will consist of a support-mounting block as an integral part of the pivoting unit with a screw attaching the arrow rest to be made from a plastic material or metal. This would allow the device to be made in one unit at the factory as original equipment. A locking screw locates the pivoting unit on the pivot shaft incorporating the biasing spring and the biasing spring adjustment knob. The biasing spring adjustment knob is held in place on the cross bar support by means of a locking screw on the first embodiment but not required on the second embodiment. The pivoting unit also incorporates the steel leaf member attached by the pivot positioning screw and lock nut. The end of the cross bar support mechanism will incorporate either the single magnet section of the first embodiment or the dual magnet sections of the second embodiment. As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the present invention.
An object of this invention is to create an arrow rest that drops down out of the way, in line with the direction of the flight of the arrow.
Another object of this invention is to create an arrow rest that drops down out of the way, without adversely affecting the flight of the arrow in any way.
Yet another object of this invention is to increase the speed with which the rest drops down.
A further object of this invention is to create an adjustment means between a spring and a magnetic force or two magnetic forces to create the quickest reaction time possible.
An additional object of this invention is to create a dependable arrow rest with repeatable performance.
These together with other objects and advantages which become subsequently apparent reside in the details of the construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part thereof, wherein like numerals refer to like parts throughout.